The cooling system uses a wax pellet-type thermostat located in the water pump. The following are the major functions of the thermostat:

A spring holds the thermostat valve closed while the coolant is cold, preventing circulation of the coolant through the radiator. At this time, the coolant only circulates through the engine.

As the engine warms, the wax pellet heats and expands against a diaphragm. This forces the thermostat to open against spring pressure, allowing the coolant to flow out of the radiator. The thermostat combines a bypass function with temperature management.